From 7df45c83903084f98589c8ab22951f2f2976f3d3 Mon Sep 17 00:00:00 2001
From: Simen Bekkhus <sbekkhus91@gmail.com>
Date: Tue, 2 Jan 2024 13:13:52 +0100
Subject: [PATCH] check lazily

---
 packages/jest-haste-map/src/index.ts | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/packages/jest-haste-map/src/index.ts b/packages/jest-haste-map/src/index.ts
index 69a5f98305c0..914513c60fc1 100644
--- a/packages/jest-haste-map/src/index.ts
+++ b/packages/jest-haste-map/src/index.ts
@@ -113,7 +113,7 @@ type Watcher = {
 
 type HasteWorker = typeof import('./worker');
 
-const isWatchmanInstalledPromise = isWatchmanInstalled();
+let isWatchmanInstalledPromise: Promise<boolean> | undefined;
 
 export const ModuleMap = HasteModuleMap as {
   create: (rootPath: string) => IModuleMap;
@@ -1109,6 +1109,9 @@ class HasteMap extends EventEmitter implements IHasteMap {
     if (!this._options.useWatchman) {
       return false;
     }
+    if (!isWatchmanInstalledPromise) {
+      isWatchmanInstalledPromise = isWatchmanInstalled();
+    }
     return isWatchmanInstalledPromise;
   }